Wow! Thanks for all the comments. I'll work on incorporating as much as I can. One problem, though, is that I'm working with RayDream 3D -- don't have Carrara, so I can't use their shaders.... Definitely good advice about dimming the lights (ambient is at zero) and adding gunk to the walls; I think I can manage those. I do have a little fog on the floor, but it's kinda covered by the text on the back cover. I'll have to try moving the stuff around. As for torches, this image was inspired by one of the tales too terrifying to tell; it takes place in a modern sewer tunnel and electric lights are specifically mentioned.... But thanks for all the ideas and compliments! - Chip